Is overpopulation mankind's most serious problem?

(This is a general debate on how serious the issue of overpopulation is to mankind. It was inspired by this post by ZPG Zealot, though it is not intended as a response to it).

Cards on the table: I’m not convinced that overpopulation is the cause of most of our problems, nor that a gradual reduction in our population would solve them. However, I confess that my knowledge of some of the issues is patchy, hence starting the thread.

I’m not sure that you can just say: Resources=fixed, Population=exponential growth, therefore: catastrophe. People have made predictions based on this reasoning many times in the past and been wrong, famously beginning with Thomas Malthus.

People will point out that there are famines, water shortages etc already. But I suspect that between ‘economic development’ and ‘fewer people’, it’s the former that would make more of a difference to the third world in these respects.

Of course our population cannot increase forever, and most detailed population estimates believe that it won’t. Our population will plateau in about 2050 at a time when much of the developing world will have developed.
The population at that time could be a frightening-sounding 10 billion…
The question of this thread is: should we expect a proportional increase in war, famine, disease, pollution etc?

FWIW I’m in favour of birth control, education etc.

any sort of “exponential” growth is occurring in several well known regions that are far, far away from where the rest of the world (Americas, Europe, East Asia) live and suffer from low birthrates and in some cases even low marriage rates. So the growth of those couple of regions is really their own, not “mankind’s”, problem - it wouldn’t be ours if the migration were minimized. As in, you know, in the event that we were to have a government that cared about our interests and all that.

It is also one of our biggest solutions too. An extra 4 billion people means a bigger talent pool of potential engineers, scientists and entrepreneurs to help us deal with our shortcomings as a species. If you cut the human population down to 2 billion you’d end up eliminating a lot of people who are trying to solve these problems.

Either way, no I don’t think our species will go extinct. We use more corn to feed livestock than we do to feed humans. With advances in agriculture it seems we should be able to feed 10 billion people. Hopefully in vitro meat will be more available by then too, which will also help us out.

I don’t think our species can or will go extinct due to resource depletion. The ‘worst’ that can happen is a culling that cuts our population numbers and/or that we get used to a lower or different standard of living.

War should keep going down as democratic reforms go up all over the world. A functioning democracy is one of the best ways to make a nation non-violent with it’s democratic neighbors.

Famine shouldn’t (IMO) be a problem. We might start seeing even more advances in agriculture due to biotech.

Yields for major field crops in major producing areas have been steadily increasing. There is no indication that the rate is slowing and no reason to fear falling crop yields. Huffman predicts that the rate of increase in yields for corn and soybeans in major production areas will rise much faster than it has in the past 50 years.

“In the case of corn, since 1955 the average rate of increase in Iowa crop yield has been two bushels, per acre, per year,” said Huffman. “That’s an amazing accomplishment starting from about 65 bushels, per acre, per year in 1955, up to about 165 bushels, per acre, per year now.”

Huffman thinks the future will be even better.

“From 2010 to 2019, corn yields are going to increase quite substantially, maybe at four to six bushels, per acre, per year,” he said.

Pollution and resource depletion will go up though. I don’t see why disease would go up. If anything it’ll go down as the developing world has more resources to conquer diseases and the wealthy world is able to invest more R&D into controlling diseases.

Some diseases like cancer will go up due to higher pollution. But there will be more and better cancer treatments too. I don’t see why infectious diseases would go up, and if they did I’m sure advances in medicine would be better at keeping them under control.

When it plateaus, I would expect things to get pretty bad.

A lot of nations base their long term economic viability on an expanding population. More people equals more consumers, for one, more people available later on to pay for debts being incurred now, plus there is a need for the younger working generations to be able to support the older generation as they leave the workforce. It seems like a pyramid scheme writ large to me, and I’ve often wondered what will happen when it eventually hits the inevitable wall. If we’re lucky when that happens technology will be advanced enough to help pick up the slack. If we’re not, I think it’s going to be a really bad time for a whole lot of people.

Childfree is the way to be.

However, the bulk of advances in the sciences and engineering have come from relatively localized societies at various points in history, and most typically those which have the most leisure time. Virtually no scientific advances have come from sub-Saharan Africa, and none of those made by the indigenous cultures of the Americas survived the holocaust that followed contact with Europeans. There’s no reason to think that a pool of ten billion people with a smattering of scientists and engineers would produce any more innovations than a smaller population of, say, a hundred million people with a greater emphasis on education and advancement in the natural sciences.

The problem with this is that all agriculture requires fresh, potable water, and this is the one resource that is truly running low. Agricultural yields are already declining in many nations that are dependent on intensive agriculture as export crops to bring in hard cash due to a reliance upon non-replenishable ‘fossil water’ aquifers and water projects that have redirected major waterflows without consideration for downstream effects. The Green Revolution permitted many nations like Pakistan to support much larger populations than it could have naturally, but continued sustenance for those populations is a real concern. This can be adjusted by using less water intensive methods of farming, but the problem needs to be addressed.

Another concern is not just the population size, but the economic and ecological footprint. We currently have industrial societies (the United States, Canada, Western Europe, Pacific Rim) enjoying a lifestyle and level of consumption that is grossly out of proportion with most of the rest of the world. As the nations of South America and Southeast Asia develop modern industrial cultures they will demand more resources per capita. This is unsustainable in the long term. Western societies have adjusted somewhat by having fewer children per family, as children are more likely to live to adulthood and are more of a fiscal liability than in sustenance cultures. We can expect cultural views to change in developing nations as well, but the question is how long that will take, and if the current growth spurt can be sustained until the population plateaus. The decline of populations also causes another problem, as most social services are predicated on an increasing population supporting the previous generation; as generations become progressively smaller in size, you’ll have fewer people supporting more, either requiring higher productivity or a declining quality of life.

To answer the o.p.: it is a significant problem, but one that will ultimately be self-correcting if we don’t step in and take measures to control it. I think our bigger problem is twofold; one, in developing the collective will to embrace and invest in cultural and technological change that will benefit the species as a whole, and finding a viable way to extend our genetic heritage beyond the surface of Earth, and hopefully someday to other stars. I have no illusions that this will be anything like fantastic space opera with people zipping about at warp speed in spandex suits, blazing away at each other with photon torpedos and blasters, but we or our successors do need to move beyond our current restraints lest some natural disaster or inevitable retirement of the species dooms us to the same fate as the dinosaurs.


I’m beginning to think the greatest threats to humanity are wannabe reality TV stars. Sooner or later one of them will be a nuclear engineer with a dream.

Generally for a country’s birthrate to increase that country must develop, economically. Dirt poor countries have high death rates. So to proliferate, countries generally must be on their way to more wealth and more leisure time.

But I don’t think increased wealth cultivates science and tech before the point where a country becomes Western-style wealthy. Poor but not dirt poor countries are still in no position to invest in higher education and R&D.

With increasing worldwide wealth, more money will likely be spent on HE and R&D, but it will mostly be in the developed world.
That doesn’t mean that the developing world is necessarily idle; it just means any sufficiently talented individuals will probably need to emigrate, for a while, if they want to work in science or tech.

This has often worried me. In Canada we have some of the highest energy usages in the world per person. It makes sense given the winter climate and the distances between population centers. The more people we have the more damage proportionally we do to the environment.
It makes sense that if we are to adjust to a static population it would be better doing it when we aren’t packed in like sardines, but at a sustainable level that hasn’t affected the environment so much. One way to accomplish this is to allow older workers to work until they want to retire. I know there is no law in Canada that says you must retire, but it seems to still be an unwritten rule. People are remaining healthier longer. It makes no sense to force them to retire before they want to. I would think that some of those jobs that we think we need new immigrants to do would be something that an older person could do quite well. I look forward to the day I can work as a Walmart greeter, once my house is paid off, and not have the stress of a more demanding job.

No. A horribly twisted distribution of wealth, and its inherent opportunities and rewards, is a far bigger problem.

According to the CIA World Fact Book, the average world fertility rate is currently 2.58. With the high death rates in some countries, that is about replacement level, or even perhaps below. Although the world population will still continue to grow for many years to come.

Unsustainable and irresponsible population growth is a problem in some countries, especially south Sahara Africa, but doesn’t seem to be a major global concern at the moment.

Why would the distribution of wealth be a a problem? Between who?

We currently live beyond our ecological means. We’re living on a ecological credit card.

There is currently a significant maldistribution of resource consumption, with the USA at something over 9 global hectares per capita and a world average of around 2.5 gha/pp.

You may ask yourself this easy question: Is it more likely countries like the USA will scale back so far that further population growth is sustainable, or is more likely that less successful countries will try to become developed? I submit the obvious answer is that we all want to live better–heck, even in the US the average guy wants to live better–and that we (the world) will all do so under the general notion that the tragedy of the commons always win when the group is large enough and inhomogeneous enough.

In short, successful countries will pay little more than lip service to leaving a smaller ecological footprint, and everyone else will try to catch up.

The question of overpopulation is not so much famine, disease and wars. It’s not even “pollution” per se. It’s a total consumption of the earth: turning every natural space into a production mechanism to support Humans.

Bob Malthus and I agree: too many peeps. He was a little more ahead of his time, and science has rendered his timing predictions premature. Right now the political climate does not permit broad-scale criticisms of population control, because most population expansion is occurring in underdeveloped countries. The successful countries use too many resources and control their birthrate; the wanna-be countries are willing to control birthrate for personal economic reasons (China, India, e.g.) but are not willing to reduce consumption until they catch up with the rich countries; and the permanently unsuccessful beggar-class countries (most African nations, e.g.) aren’t ever going to catch up but will certainly continue to increase resource consumption as fast as someone can help them consume.

(I assume you meant “…country’s birthrate to decrease…”)

It’s true that successful and resource-intensive countries have lower birthrates, and the extrapolation from this is that the (most politically-correct) way to get underdeveloped countries to stop procreating is to get them rich(er).

The problem is that you cannot get them richer without increasing their ecologic footprint, be it CO2 or farmland or anything. In the end wealth basically drives consumption of resources and consumption of resources vastly outpaces the ability to provide “stuff” in a totally ecologically neutral fashion.

So…to get the population under control by getting the unsuccessful populations rich, you vastly increase the strain on the earth.

Because the huge majority of the world’s money lies in the hands of a very small percentage of the global population.

Have you previously not heard of the starving billions of people around the world living in poverty?

So, taking the money from all those rich people would keep the billions of others from starving? And by ‘rich people’ that probably means you and I, too.

Reducing population to more sustainable levels will not solve the world’s problems, just keep them from intensifying to even more dangerous levels. Critical water shortages and climate change are two examples of issues that can be mitigated to some extent by curbs on overpopulation.

You…you anti-natalist you! For shame!

No kidding it means us. It’s not simply about taking the money… the damage is done, now there needs to be some way of correcting it.

Yes, but you and I didn’t cause some schlub in deepest, darkest Africa to be poor. His problems are closer to home. It doesn’t matter how rich we become because we aren’t stealing from him to do it, or denying him the opportunity to better himself.

Actually I meant “…country’s population to increase”.
Phase 2 of demographic transition is high birth rate but decreasing death rate as a country becomes able to afford better healthcare and nutrition.
So (generally) countries must get a little wealthier before their populations can balloon.

Worse than that is me pushing my pro-education agenda.
I should start a thread: “Education – for or against?”